Transition Metal Doped NiO on Modified Carbon Felt for Overall Water Splitting

ABSTRACT The global energy landscape is undergoing a transformation to address fossil fuel reduction, climate change, and environmental degradation. Hydrogen‐based fuels are a promising solution, where hydrogen serves as a clean, versatile, and sustainable energy carrier, typically produced via the electrochemical splitting of water into oxygen and hydrogen, comprising the oxygen evolution reaction (OER) at the anode and the hydrogen evolution reaction (HER) at the cathode. Here, transition‐metal (TM)‐ doped NiO is deposited on modified carbon felt (MCF) substrates by chemical bath deposition (CBD) and evaluated for OER, HER, and overall electrocatalytic performance. The surface characteristics are analyzed using energy‐dispersive spectroscopy integrated with scanning electron microscopy (EDS‐SEM). The electrocatalytic behavior of NiO@MCF is examined and compared with TM‐doped NiO@MCF prepared by the same procedure. The results reveal that MnNiO@MCF is an efficient system, exhibiting overpotentials of 105 and 111 mV at 10 mA cm − 2 for OER and HER, respectively, and a cell potential of 1.51 V for bifunctional operation. Furthermore, similar LSV properties are observed after 12 h of chronoamperometric (CA) testing, with an overpotential of 200 mV. These findings highlight MnNiO@MCF as a highly effective and promising electrocatalyst for overall water decomposition, with strong potential to enhance the efficiency of hydrogen production.